Tom Nook's store is the economic centerpiece of every player'stown. The store is owned and operated by Tom Nook, the most important non-playable character in the series.

In Animal Crossing and Animal Crossing: Wild World, Tom Nook stocks items based in Groups (A, B or C). The player's town is designated a group, and items from that group are more likely to stock in the store. Items from other groups will stock as well, but less frequently. The only way to find out what group the player's town has been designated is for them to keep a tally of the number of items from each group. Item Groups do not exist in Animal Crossing: City Folk, items are available based on individual towns. When the shop is about to upgrade, a message will be posted on the Bulletin Board which will aunnounce the store's closure the next day.

Tom Nook's store made its first appearance outside of Japan in the Nintendo GameCube Animal Crossing, as did many of the items sold at his store. The store was randomly located on the map of each town, but, like the Post Office, could only be found in the 'A' acres. The store offered furniture, clothing, tools, flowers, tree saplings, carpet, wallpaper, paint, and sign boards in exchange for Bells, the currency of the Animal Crossing world. The store is open from 9am to 10pm, except Nook 'n' Go, which is open from 7am to 11pm.

At the beginning of each game, the player will have a part-time job at Nook's Cranny to help pay off their mortgage. This will involve making deliveries, writing letters, and meeting the residents of the town. While working for Nook, the work uniform is obtained. This outfit is rare and it cannot be obtained from anywhere else or ordered from the catalog, but it is worth nothing.

After finishing the tutorial part-time work, the player is able to sell various items to Tom Nook in exchange for Bells. In many respects, these transactions form the core of the game experience.

Wild World also featured Nook's store randomly placed, but as the acre system was discarded for this title, the store may be located anywhere in the town. Furthermore, it will always be accompanied by Mable and Sable's clothes shop directly to the east. All upgrades of the store have opening hours of 8am to 11pm.

Several minor changes were made for this title. The sign board item is no longer offered, though other tools have been added. Nook also does not sell clothing or umbrellas in this title, except via catalogue; one must purchase shirts and other accessories next door from the Able Sisters.

Shampoodle was also featured in Nook's shop in Wild World, operated by Harriet as a hairdresser in the Nookington's upgrade.

While the store is once again located randomly, it is no longer tied to the Able Sister's shop. Store hours for the Nook 'N' Go upgrade were changed, with the store now remaining open until 1am. The Tom Nook Point System was revised to include a gift exchange feature, so that points can be exchanged for rare items. The Shampoodle was moved from Nook's to the city in this title.

Interestingly, this title also features the thus-far unique ability to have Nook downgrade his store. Thirty days after the player obtains Nookington's, as they are exiting the store, Nook will ask if the player favors good hours, a balance, or variety. The player's response will cause him to downgrade to Nook 'n' Go, downgrade to Nookway, or keep Nookington's, respectively. Any change, if requested, will happen a week later. If the store is changed, Tom Nook will ask his survey again, after another thirty days.

A noteworthy item that Nook will buy is the white turnip, an item that may be purchased by the player from Joan on Sunday mornings between 6am and noon. This particular transaction is notable because the price Nook will pay varies from day to day, forcing the player to follow the Stalk Market. Tom Nook will not buy white turnips on a Sunday, saying that the stalk market is 'closed'.

Aside from selling items in the store, Nook also gives the player access to their own personalized catalog, from which the player can order most items that they have held in their pockets. Most items that were ever held there will be featured, but rare items, fossils, gyroids, etc. cannot be ordered. When purchased, an item will arrive by mail at the next 9am or 5pm delivery time (or the next time the player plays the game in Animal Crossing). Only five items may be ordered at a time between mailings.

In Animal Crossing, Nook offers a raffle for three rare items on the last day of every month. These items can only be obtained through the monthly raffles. One entry for a chance to win requires five raffle tickets. Tickets are given to the player by Nook during the month after the purchase of an item in the store (not for items ordered through the catalog). The tickets are only good for the month they are labeled for but can be used in the future if saved. Nook will only give out raffle tickets for purchasing certain items. Items that will give the player a raffle ticket are clothes, umbrellas, furniture, wallpaper, and carpet. On raffle day, the player cannot buy or sell items at the store.

When buying items in the store in Wild World and City Folk, Players are awarded Nook Points. For every 100 Bells spent, the Player earns 1 Nook Point. However, this is not cumulative: i.e. buying a pack of seeds at 80 Bells gives zero Nook Points, buying two for 160 Bells will still give zero Nook Points since they were purchased separately. In Animal Crossing: City Folk, players can earn 3 points each day by selecting 'visitor points' at the machine, or 5 if this is done in another town. They may also trade points for Nintendo-themed prizes.

Nook Points serve to reward players for shopping at Nook's, offering discounts and prizes for their loyalty.

The easiest method for accumulating points would be waiting for when Tom Nook has a "5 times Point Day". These days, which are announced on the town message board, any item will award five times the normal point value. A normal purchase of an item at 100 Bells will now give the player five points during these days. Items ordered from the catalog will work as well. During these times, a moon will give the player 1,600 points. This means, to get Platinum membership, the player must pay 400,000 Bells. That would normally get the player 4,000 points, not even enough to reach Silver membership.

Nook's Cranny is the first incarnation of Tom Nook's store. Open from 8 a.m. to 10 p.m., the player begins the game with this store. The player must spend and/or sell a total of 25,000 Bells and play for at least eight days for an upgrade.This was renamed Nookling Junction in Animal Crossing: New Leaf.

Nook 'N' Go is the second of Tom Nook's shops in the Animal Crossing series. For Tom Nook to expand to this shop, the player will need to buy/sell 25,000 Bells worth of stock at Nook's Cranny and, in Animal Crossing: City Folk, play the game for at least 8 days. It is the only shop that has a sign pole. This shop is also the one that is open latest, and earliest (From 7:00am - 11:00pm) (Animal Crossing) and from 7:00 am to 1:00 am in City Folk. In Wild World, the store opens and closes at the same time as the other stores. The store was renamed T&T Mart,and changed a bit in New Leaf.

Nookway is the third expansion of Tom Nook's shop. For it to open, the player needs to buy/sell 65,000 Bells at the previous Nook stores combined. It has a wider variety of items to choose from. This shop follows Nook 'N' Go. It is the second shop to have an automatic door. The store was renamed Super T&T and changed a little bit in Animal Crossing: New Leaf.

Nookington's is the largest expansion to Tom Nook's shop. In this expansion a new upper floor appears where furniture, wallpaper, and flooring are sold by Timmy and Tommy, as well as the normal ground floor Tom Nook still runs. In Wild World, it also contains Shampoodle, which provides hairstyle makeovers for players at the cost of 3,000 bells.

To get Tom Nook to expand his store into Nookington's in Animal Crossing (GCN) and Wild World, the player must buy/sell 240,000 bells and have a friend shop at the store. In City Folk, players do not need a friend to shop at Nookway, and players need to buy/sell only 150,000 bells for Nook to upgrade to Nookington's. Nookington's was completely changed and renamed T.I.Y. in Animal Crossing: New Leaf. In that game, there was another upgrade called T&T Emporium.